ISO 12406:2010 specifies a secondary-ion mass spectrometric method using magnetic-sector or quadrupole mass spectrometers for depth profiling of arsenic in silicon, and using stylus profilometry or optical interferometry for depth calibration. This method is applicable to single-crystal, poly-crystal or amorphous silicon specimens with arsenic atomic concentrations between 1 x 10¹⁶ atoms/cm³ and 2,5 x 10²¹ atoms/cm³, and to crater depths of 50 nm or deeper.